1. Field of the Invention
The disclosed invention relates to the computerized control of a pumping system that permits automatic monitoring and subsequent on demand removal of fluids.
2. Brief Description of the Prior Art
Several different pumps are available to pump oil and water. The most widely used method for pumping oil is by using a pump jack (beam pump) connected to rods and tubings. Methods using air to propel fluids to the surface are airlift pumps, compressed air centrifugal pumps, and air pumps, which require pressures sufficient to overcome the hydrostatic head of the fluid in the hole.
Pump jacks are relatively expensive, bulky, and because of the weight of the unit, a crane or hoist is necessary when the unit is installed, removed, and serviced. Usually, these units are powered by electric motors, and the efficiency of lifting oil by this unit in the field is very low, usually less than one percent.
The air lift system is simple in use, but it depends on the relative densities of fluid and/or air-fluid mixture and for deeper wells, the required pressure and volume of air is quite large. In addition, the air in this system often emulsifies the oil. A typical airlift system is described in U.S. Pat. No. 759,706. Anthony et al. U.S. Pat. No. 4,092,087 also discusses a very complicated air operated pump, where compressed gas or air in the range of 25-350 PSI is utilized with a large float to cause the pump to force the fluid up a tube. This complicated construction is obviously quite expensive.
Air pumps have been designed such that the fluid passes through a ball valve located on the bottom of the pump tank. U.S. Pat. No. 919,416 to Boulicault and Japanese Pat. No. 5681299 by Nakayama discuss such a system with an air tube connected to the top of the tank and a fluid discharge tube extending to the bottom of the tank. After the tank fills with fluid flowing through the bottom ball valve, air pressure is applied to the air tube, which closes the bottom valve and forces the contents of the fluid up the discharge tube. If the fluid level is several hundred feet or more above the pump, considerable air pressure is necessary to overcome the hydrostatic level of the fluid to close the bottom valve and even greater pressure is required to force the fluid to the surface. McLean et al U.S. Pat. No. 3,647,319 employs a similar method with the addition of a ball valve in the fluid discharge tube to prevent the fluid in the discharge line from returning to pump tank. This unit requires rather large air pressure to elevate fluid from deeper wells. In column 3 of their patent, they state that full discharge will occur from any depth within range of 0 to 300 feet. At a depth of 1,000 feet below the top of the fluid, a pressure of about 460 PSI and a large air volume will be required to discharge water from that borehole.
Although progress has been made in the apparatus to pump oil or water from a borehole, the systems generally operate on a timed basis, pumping whether or not oil or water is present. This places increased wear on the apparatus as well as uses valuable energy. The prior art systems require a pumper to visit onsite to verify that the system is working properly. Further, prior art systems have not provided the safety measures that are important to protect our environment. The instant disclosure provides a computerized system that controls and monitors the pumping and storage apparatus of multiple wells to provide on demand pumping. The monitoring capabilities further provide safety features that help to prevent oil leaks or thefts, while using minimal running energy.
The invention discloses a system for controlling one or more borehole pumps to enable pumping-on-demand. The system uses a computerized controller, which in combination with sensors, monitors and controls the activity of the pump, thereby controlling fluid in the borehole. The system is continually in one of three modes. The majority of the time the system is in Mode One, the monitoring mode, during which the system is waiting for fluid to be detected, or some other appropriate initiator occurs. Once the initiator, such as a fluid, is detected by the system, the controller will start Mode TWO, the initiation of the pump cycle. Mode Two, the pump mode, begins with the application of propellant gas and ends when the fluid slug is detected at the surface, signaling the controller to terminate the application of the propellant gas. At this time, the controller enters a system recovery period, or Mode Three. This recovery period allows time for the propellant gas pressure to be recharged, pump chamber pressure to equalize with the bore hole pressure, the chamber to recharge with bore hole fluid, and time for the down-hole sensor, if employed, to stabilize.
Within each cycle of modes, the system performs multiple checks on the apparatus involved. The data obtained during the check is store d in appropriate databases as well as checked against predetermined norms. In the event of a malfunction within the apparatus, or other supervised and/or monitored functions, the system can activate a notification system, such as a centralized monitoring facility.
The pump disclosed for use within the system comprises a pumping chamber and a U-shaped chamber proximate one end of the pumping chamber. A valve system extends from the pumping chamber into the U-shaped chamber. The valve system is a hollow polygon having at least one valve seat containing a valve passage. A check ball blocks the valve passage during the pumping mode and permits fluid to flow into the pump chamber during the monitoring mode. The U-shaped chamber contains fluid inlets to enable fluid to enter the U-shaped chamber and flow through the valve passage into the pumping chamber. A propellant line is affixed to the pumping chamber to provide access for propellant to enter the chamber and push the fluid out through a fluid return line. The fluid return line extends into the chamber at one end and leads out of the borehole to a fluid depository, such as a storage tank. A fluid sensor within the chamber detecting the presence of fluid within the pumping chamber. A slug sensor can be located either proximate the pump or at a remote location to detect the beginning and end of a predetermined quantity of fluid.
An exterior housing can be placed over the borehole to contain the monitoring computer and associated read outs. A lightning protector, consisting of a ground electrode adjacent an electric service riser. A pair of ground wires, one affixed at one end to the electrode and at the other end to the exterior housing and the second affixed at one end to the housing and at the other to the computer and a faraday shield.
At least one shunt valve is affixed along the propellant and return lines inline. The shunt valve has body containing a recessed receiving area, a propellant line channel, a fluid return line channel, and a connection passage between the channels. A powered cylinder, with input and output connectors, extends into the body adjacent the receiving area. A series of connection hoses are connect to the cylinder inputs and outputs to connect multiple shunt valves. A valve plate, pivotally connected to the receiving area has an open port and is affixed to the powered cylinder to pivot the port in and out of alignment with the connection passage in response to movement of the cylinder. A cylinder activation member activates movement of the cylinder in response to coming into contact with borehole fluid.
A receiver/separator tank has a base with multiple connectors, a fluid housing in contact with the base, a separator cap, an electronics housing proximate the separator cap and a housing top. A fluid outlet tube is connected to one of the multiple connectors to transport fluid collected in the base. A gas pipe extends into the housing and exits the base to remove gas separated from the fluid. A safety line, having a pressure relief valve at the base of the housing, extends into the house proximate the gas pipe. A propellant supply line extends into the tank to connect, through a 3-way valve, to the supply line leading to the pump. A liquid return line brings fluid from the borehole into the housing to be separated from any gas contained in the fluid. The separator, at the end of the liquid return line is spaced from the separator cap and has a T-connector with angled outlets. The angled outlets direct the fluid at an angle to fall to the base where it is removed. At least one sensor within the tank communicates with the controller. The sensors are placed within the tank at different heights. The 3-way valve has a supply line connector, a propellant line connector and an exhaust line connector. A moveable member alternates the connection between the propellant line and the exhaust line and supply line to connect the propellant line to the supply line in a first position and the propellant line to the exhaust line in a second position.